I think it is an easy fold after his all-in. But what about my raise on the flop? It seems risky: There aren't many hands that I beat (TT, 99, maybe also JTs), there are some more beating me (AJ, 88, QQ+). Also he plays sandwiched against four opponents so he is less likely to bluff.

For just that reason I don't like raising in those spots, rather just Call it and reevaluate on further streets. With raise you are turning your hand into bluff while we still have showdown value, we kinda have to fold when he 3bets us.